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Fencer Intel
high 7.5

CVE-2026-118747 json

.NET Denial of Service Vulnerability

published yesterday modified 17h ago also EUVD-2026-122253 , GHSA-vmv3-wvjp-wqpj

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits
0
none known

Summary

Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.

Patch / fix

  • nuget System.Formats.Cbor 8.0.2, 9.0.24, 10.0.15, 11.0.0
  • Microsoft System.Formats.Cbor 9.0.24

Is CVE-2026-118747 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
yesterday

Exploit prediction

1.30% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
nuget System.Formats.Cbor
>=8.0.0-0, <8.0.2
>=9.0.0-0, <9.0.24
>=10.0.0-0, <10.0.15
>=11.0.0-0, <11.0.0
8.0.2
9.0.24
10.0.15
11.0.0

Affected products

  • Microsoft System.Formats.Cbor

Classification

Weakness
  • CWE-407 Inefficient Algorithmic Complexity

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.